I've been working with TypeScript a lot over the past year and prefer it to some other languages now(like Python). I would still probably prefer C# and dotnet; all the way if it ran in the browser.
* .Net is faster
* ASP.NET Core is faster
* .Net uses thread pools for task scheduling; parallelism
* Run time type information
* An mostly complete task(async/await) based stdlib(node hasn't even started on this to my knowledge)
* Linq -> fantastic
* Entity Framework -> not without some quirks, but fantastic
* Roslyn; feeding dev-time code generation back into your compiler/tools allows for some really cool IDE aware tooling.
* Cool JIT/IL stuff like Jil
* More number types than "number"
* etc
I don't mean this as criticism, I'm working on some Node/TS projects and I'm very interested to hear the strengths .NET has over Node.